2012 Jeep Wrangler JK Factory Service Manual 28 - DTC-Based Diagnostics

U0404-IMPLAUSIBLE DATA RECEIVED FROM ESM

U0404-IMPLAUSIBLE DATA RECEIVED FROM ESM

For a complete wiring diagram, refer to the Wiring Information.


Theory of Operation

The messages sent on the CAN bus are distinguished by an identifier (ID). Each CAN ID is defined to contain a certain number of bytes. The Transmission Control Module (TCM) verifies that it has received the proper number of bytes for each ID.



Possible Causes

TIPM CAN BUS DTCS PRESENT
ELECTRONIC SHIFT MODULE DTCS PRESENT
TRANSMISSION CONTROL MODULE

Always perform the NAG1 Pre-Diagnostic Troubleshooting procedure before proceeding. (Refer to 28 - DTC-Based Diagnostics/MODULE, Transmission Control (TCM) - Standard Procedure).


1. CHECK FOR TIPM CAN BUS DTCS


1. With the scan tool, read TIPM DTCs.


Are there any TIPM CAN BUS DTCs present?

Yes


No


2. ELECTRONIC SHIFT MODULE DTCS PRESENT


1. With the scan tool, read Electronic Shift Module (ESM) DTCs.


Are there any ESM DTCs present?

Yes


No